This course provides an overview of the issue of postharvest loss of grains by exploring essential physical, technical, and social dimensions of postharvest supply chains and loss prevention methods globally.
Each year, estimates suggest that 1/3 of all food produced is lost or wasted, making postharvest loss a critical global food security and sustainability issue of today. Key knowledge areas are presented including:
-An overview of postharvest loss
-Supply chain activities such as harvesting, drying, and storage
-Economics and markets
-An introduction to the network of actors working in this field
We face the immense challenge of feeding over 9 billion people by the year 2050. To meet these demands, yields will have to more than double using the same amount of natural resources. In recent years, postharvest loss has been recognized by major institutions including the US government, the United Nations, the CGIAR Research Consortium, and several others as a significant opportunity to impact food security and improve livelihoods. Despite this increased attention, a lack of knowledge, technical capacity, and resources remain obstacles for stakeholders worldwide to act on these issues. This course will, for the first time, provide you as professionals, practitioners, and students, with a comprehensive introduction to postharvest loss processes and begin building capacity for loss prevention worldwide.

Taught By

Dr. Prasanta Kalita

Director of the ADM Institute for the Prevention of Postharvest Loss

Transcript

My name is Steve Sonka, I'm an emeritus chaired professor of agricultural strategy at the University of Illinois. And I'm also serving as a research professor for the ADM Institute for the Prevention of Postharvest Loss. Today I'd like to talk to you about postharvest loss but more importantly about mitigating postharvest loss and I'm going to take a bit a systems perspective. Since about 2011 when the ADM institute was established with a generous gift by the ADM corporation. We've been trying to understand the dynamics and what causes postharvest loss to occur, in a food and agricultural system context. And then, what can we do to mitigate postharvest loss, thinking about that systems perspective? These are important words, they're emotional words. Another priority in the poorest countries must be to reduce the tragic waste of losses after a harvest from inadequate storage, transportation, and pest control. We urge a goal of cutting in half those post-harvest losses. Now that seems like it could have been written up at a conference last week. But in fact this was done in 1975, and the goal was to cut postharvest losses in half by 1985. Now this was not just a trivial college professor saying what we ought to do. This was actually a statement by Henry Kissinger. And Henry Kissinger at the time was the Secretary of State for the United States. A very influential diplomat. He's well known for many things besides talking about postharvest loss. In fact he's typically held as being primarily responsible for opening China and the United States in the mid 1970s. This goal was adopted as a resolution of the UN general assembly in September 1975. Now if you're interested in systems, you think about questions. And so things that come to mind in my mind about questions are have we? Have we cut postharvest loss in half? Most people, when I ask this question, in the audience say no. And I agree with them. And then the question becomes why not? And I think it's because we've not been prone to think about this opportunity, this problem. As, in the context of the system with which it exists. And that's what I want to talk about, and I want to frame these remarks around three questions. What hasn't worked? What has worked, and how do we enable better decisions? Because it's decisions that fundamentally change the system to allow for postharvest reduction, postharvest mitigation, to occur. And so that, I want to frame these remarks around those three questions. So let's think about what hasn't worked. And I'm going to take us for a minute to a place which is well known for a fabulous transformation of agriculture. In the 1970s the Mato Grosso state in Brazil, which is in the center west part of Brazil. Was known as a place where there would be a few ranches and a few cattle and not much else. This wasn't the tropics of the Amazon it's actually south of the Amazon, it was populated by scrub brush. In the 70s, 1970s soybeans came to Mato Grosso, tremendous innovation, tremendous linking of research, farmers, agribusiness industry. Mato Grosso is now clearly the second largest producer of soybeans in the world. When you think of Mato Grosso, you may have seen pictures of ten combines going across a field, harvesting soybeans in this field that doesn't seem to end forever. That's Mato Grosso. Big industrial agriculture. But lets look at some scenes from postharvest loss in Mato Grosso. And what you're looking at there in the bottom of that picture are soybeans. Soybeans laying on the ground that fell off the trucks on the way from the field to the export port or to the harvest site. When Brazilians come to the United States and drive around in Illinois or Iowa or Ohio, Indiana, looking at harvest of soybeans, one of the things they notice is there's no soybeans laying along side of the road. I have been in a car in Mato Grosso driving down the road with soybeans bouncing off the hood of the car from the truck in front of me. And so this is a very, very typical scene in postharvest loss. Why does this occur? Well, I want to say that it's because we naturally, not just farmers in Mato Grosso. But we naturally tend to think about the visible outcomes, which in systems context we call events we focus on the grain on the side of the road. The grain on the side of the road is a symptom. Okay? It's not a cause of the problem. It's a symptom of the problem. We need to look below that. And then we tend to look at patterns. Well, the patterns of soybean production in Mato Grosso changed over the last 40 years. To where now every year the farmers in Mato Grosso plant a soybean crop and then plant a corn crop. But they have to get the corn crop planted in January and February because the rains stop in March. And when the rains stop there is no sense planting a corn crop. Or a maize crop in Brazil. Where most places around the world that refer to maize, not corn. So we'll talk about the maize crop. So there's tremendous time pressures on everybody in the system in Mato Grosso at the soybean harvest, because there's this passion and economic need to get the maize crop planted. So that has caused tremendous pressure, where speed is of the essence. Beyond that there are kind of structural issues. In the United States in a very similar kind of agriculture, same technologies, same seeds, same combines, same contractors. The structure of agriculture is such that there are many local elevators. And there's many small silos on farms where the farmer stores there own grain. And so you ask why don't you do that in Brazil. In Brazil, in Mato Grosso, those trucks are going 1,000, 1,200 miles to the port. Again, pressure on the system causing loss. Well for years the government agricultural loan policy would provide low cost loans for movable equipment, but not for structures like grain bins. Now this has changed in the last year or two, and we expect to see a lot more grain bins created in Mato Grosso or established in Mato Grosso as a response to that. The change in structure. So as we think about wherever we see postharvest loss. Whether it's in Mato Grosso, whether it's in fresh fruit in India, whether it's in teff, an important staple crop in Ethiopia. Or whether it's maize in Ghana. We need to find the structure. The structure that's causing the problem not just the events. So I wanted to really emphasize the point of we tend to see the symptoms and try to respond to the symptoms. But it's the causes we need to be addressing and we need to find those causes. I'm going to do just a couple minutes here from a very recent study, looking at different technologies in Uganda and Burkina Faso. And the issue here was, could small holder farmers in those countries adopt technologies to reduce postharvest loss? In the upper left hand corner we see gunny sacks, jute bags, which is a traditional type of storage. Which we'll see in a minute has a considerable amount of loss. We're looking at five alternative technologies that were tested, in the lower left hand corner. We see metal silos, then next to that plastic silos, something that's called hermatic storage in superbags. As we move up to the upper right hand corner, we see some what are called zero-fly bags. And then we see some very large bags. That are also hermetically stored that provide storage protection from pests during the storage cycle. Now we're going to look at some results. And in the left hand corner we're looking at losses from traditional storage. And so we have a blue bar and what that blue bar indicates that in this pilot test, 21% of the grain was lost if the grain was stored for just 30 days. If the grain was stored on-farm by farmers for 60 days, losses went up to 37%. If the small holder farmers stored the grain for 90 days, losses went up to almost 60%, 59.8%. Now, the reality is small holder farmers don't store grain. Because if they stored it in traditional storage, they would lose most of it. So the common practice in these countries is to sell grain at harvest. Unfortunately, that's when prices are lowest. More unfortunately, often times the farm family needs this grain for it's own consumption. Which means, as the year progresses, they're buying back the grain at high prices that essentially is the same as the grain they sold at low prices. So that's why storage is so interesting. The next five group of little round circles represents the same results for the technologies we looked at on the previous slide. I'm not going to go into those in any depth. The reality is that the worst performing alternative technology was 98 % better than traditional technology. So it really leaves the question which technology is useful? But it's not really the fundamental question. The fundamental question is what's needed so that small holder farmers can make decisions to adopt technologies which show such marked improvement in a reduction of postharvest loss.

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